Core C: Much of the WLS data required for the WLS program of projects is already in hand or will be collected in proposed telephone and mail surveys. However, several additional data collection activities are essential for the projects proposed herein or for other related projects that are being proposed independently. These data will extend the range of research that WLS participants and other scholars may undertake using the WLS and related data resources. We will centralize these activities in a single project core in order to share staff and other resources, to coordinate sampling designs across complementary activities, and to assure quality data matching, management, security, and documentation. All supplementary data will be equally available to WLS projects and to public data users, either directly or through our secure data enclave. The goals and activities of the Core are summarized in the following specific aims: (1) matching WLS records for graduates and siblings born in Wisconsin to official birth records; (2) linking records of WLS graduates, siblings, and parents to additional years (post-1998) of the National Death Index (NDI-Plus); (3) collecting bio-medical data and bio-markers from sub samples of graduates and siblings; (4) linking WLS records to the Wisconsin state tumor registry; (5) conducting a survey of Wisconsin health insurance plans; (6) linking respondent locations to local health resources using the .Area Resource File and Interstudy data; (7) linking older siblings' records to Medicare enrollment and claim data; (8) collecting and linking data on elementary schools attended by the graduates (from Wisconsin state historical archives); (9) linking WLS records to Wisconsin Worker's Compensation records; (10) linking WLS records to SSA earnings and disability benefit records; (11 ) completing the geocoding of addresses of WLS participants throughout the course of the study and linking them to local area data.